Many readers may have in their possession a diamond (or many loose diamonds) accompanied by a GIA Diamond Grading Report and are well versed in the content of the Certificate. A graphic image of a GIA Diamond Grading Report is produced here and a brief description and comments will add on to your further understanding of the said report.
Report Date: The date should be as current as possible. A report dated many years back is still valid, no question about it. However, mishandling of the diamond over the years may result in some tiny chips especially around the girdle, where it is the most vulnerable and would thus down-grade the diamond.
Laser Inscription Registry: The alpha character of GIA followed by many numerals are the inscription being laser-ed across the girdle. This can be viewed carefully using a 10X loupe. When you purchase a loose diamond and request the store owner or you want to send it to your friendly jeweler for setting, you must ensure that one of the prongs in your ring or pendant do not hide or obscure the laser inscription. Diamonds with laser inscriptions are seldom bezel set as it will cover the girdle completely.
Shape and Cutting Style: Round Brilliant
Measurement: This is measured in the metric system in millimeters. The first 2 measurements are the average diameter of the round. The closer they are the better for this denotes the exact roundedness of the diamond for a Brilliant Cut. In this said example, the difference is 0.02mm, which is 0.3% of the overall diameter and is negligible. However, one must not be too overly concerned on this unless the two measurements are miles apart, in which case the Cut Grade will tell you that the cut is Fair. The last measurement is the depth of the diamond.
Carat Weight / Color Grade / Clarity Grade: Self Explanatory. For further information refer to this post, Costly Crazy Carbon Crystals – The 4 Cs of Diamond.
Cut Grade: This is not the shape of the diamond. Cut is what we call ‘make’ of the diamond. It defines how well and how proportionate is the cutting to bring out the fire and brilliance of a diamond. The grades are Excellent, Very Good, Good and Fair.
This certificate denotes that the diamond is perfectly cut to what is known in the trade as Triple Excellence. A 3X diamond commands a premium and may sell above the price of a Rapaport Report.
Fluorescence: None. A diamond’s fluorescence is determined as None, Faint, Medium, or Strong based on its reaction to ultraviolet light.
Key To Symbols: This is the graphical representation of the inclusion found within the diamond.
The exact proportion of the said diamond being graded is represented by the diamond icon which is described as ‘Profile to actual proportions.”
GIA also issues the GIA Diamond Dossier on a half A4 size paper, full fold. It contains the same grading information as the GIA Diamond Grading Report but without the plotted diagram. As an added security feature, the Dossier service includes a microscopic laser inscription of the report number on the diamond’s girdle.